Physical Properties Of Natural Gas
[B]Physical Properties Of Natural Gas - I[/B]
This calculator takes in the fractional molar compositions of the natural gas (and gaseous impurities, if any) and outputs estimates of 2 physical properties of natural gas - [B]Real gas deviation factor (Z) and Gas viscosity (μ)[/B], as well as the [B]Specific gravity (sg)[/B] of the gas. The 2 properties are listed and plotted for the specific temperature and pressure entered as well as for pressures in the range zero to 5000 psia.
[B]Z-factor[/B] is computed using the [B]Hall-Yarborough[/B] direct method. This consists of 2 equations:
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[B]where:[/B]
ppr = pseudo-reduced pressure
t = reciprocal of pseudo-reduced temperature
y = "reduced" density (an unknown).
The gas composition values are first used to determine the constants in the equations (specific gravity, critical and pseudo-reduced pressures and temperatures). The second non-linear equation is solved for "y" using the [B]Newton-Raphson[/B] iterative technique, and the result is plugged into the first equation.
Finally, [B]Gas viscosity[/B] is computed from the correlations by Carr et al.
